An HDMI is an interface/standard that develops a Digital Visual Interface (DVI) which is an interface standard of personal computers and displays for a use of AV electronic products. Since the HDMI transmits video/audio from a player to a display device without compressing it, there is very little latency between a source device and a sink device. And the HDMI has high format compatibility since the HDMI does not require separate decoder chip or software.
As UHD TVs are spreading, UHD contents are now being distributed in various forms of storage media and through various services to provide the users with a vivid sense of realism and immersion through UHD TVs. The user can enjoy UHD contents in uncompressed video by connecting an external source device such as a UHD TV, set-top box, and Blue-ray disc player via a wired video interface such as HDMI, DisplayPort, and the like.
The conventional high-speed interface transports video and audio data from a source device that provides contents to a sink device that displays contents. However, according to the evolution of a sink device like a TV, there is the need to forward data in the reverse direction to the direction in which video and audio data are forwarded.
The sink device that is available to connect a Human Interface Device (HID; e.g., a keyboard, a mouse, etc.) as well as a touch function utilizes the Universal Serial Bus (USB) interface for forwarding the data received from touch data or a Human Interface Device (HID) to the source device. That is, independent of a high-speed interface for forwarding video and audio from the source device to the sink device, a separate USB interface is required for forwarding touch data or HID input data from the source device to the sink device. This acts not only as a factor for increasing hardware complexity and price but a user is unable to use it intuitively, and accordingly, causes an inconvenience in use.
Accordingly, a method is required for transmitting touch data and/or HID data input from a sink device through a high-speed interface to a source device.